The invention relates to a device for applying a viscous fixing medium to electronic components, more particularly to chip-type components, comprising an elongate bin with a container for the medium, and a plurality of stamps the stamp heads of which are directed vertically upwards and which are arranged in a regular geometric pattern, their lower ends being coupled to a common driving element. The stamps are displaceable in a vertical direction between a lower rest position in which each stamp head is situated in the container below the level of the medium, and an upper working position in which each stamp head projects above the container.
Such a device is known from European Patent Application EP No. 0 071 303 A1, to which U.S. Pat. No. 4,480,780 corresponds. This known device serves to apply glue simultaneously to the lower side of a plurality of electronic chip-type components, which have been temporarily brought to a standstill over a bin containing a fixing medium and which are positioned with respect to the stamps. In this known device, all stamps are identical, are rigidly secured to a driving rod and have a stamp head of the same shape.
The range of chip-type electronic components, without the conventional comparatively long connection wires and suitable to be mounted on substrates devoid of holes, becomes gradually wider. An increasing number of types and kinds of components are adapted for so-called surface mounting on substrates devoid of holes. The variety of chip-type components, both with regard to type and with regard to shape and dimensions, still increases. As to the dimensions of the components to be processed, dimensions are to be considered which lie in the millimeter range; a frequently occurring type has the dimensions of 0.8.times.1.6.times.3.2 mm. As to their shape, the chip-type components can also be greatly different: the most frequently occurring components are block- or plate-shaped; however, cylindrical components are also known.
As is known and as has been described in the aforementioned European Patent Application EP No. 0 071 303 A1, these components are fixed temporarily onto the substrate by means of a fixing medium before they are soldered ultimately on the substrate. For this purpose, a quantity of fixing medium is applied to the lower side of the chip-type components by means of the device known from the European Patent Application. It has now been found that specific requirements apply to every kind of chip-type components as to the shape and the volume of the applied quantity of fixing medium; it has been found in practice that, in order to obtain a reliable adhesion of the component to the substrate, without the track pattern on the substrate being contaminated with the fixing medium, for every kind of chip-type components a given optimum quantity of fixing medium is necessary, which has to be applied to the component in a given form. These requirements cannot be satisfied when the known device is used.